If your TCL window air conditioner is building up ice or frost, it usually isn’t dangerous, but it does mean the unit isn’t working as efficiently as it should. This guide will help you understand why it happens and what you can safely try at home.

What does “freezing up” look like?

You may notice:

• Ice or frost on the front grille or around the air vents
• Ice on the metal coils behind the front filter
• Very little cool air coming out, even though the unit is running
• Water dripping inside when the ice starts to melt

If you see sparks, smell burning, or hear loud popping noises, turn the unit off and unplug it right away and contact TCL support.

Why window AC units can freeze up

Common reasons include:

• Dirty or clogged air filter – Air can’t move through the unit, so the coils get too cold and ice forms.
• Airflow blocked – Furniture, curtains, or blinds blocking the front of the AC.
• Fan speed too low – Very cold air sits in the unit instead of moving into the room.
• Temperature set too low – Running the AC on the coldest setting for a long time can cause icing.
• Outdoor temperature too low – Most window AC units are not designed to cool when it’s cool outside (for example, below about 60°F/16°C).

Step 1: Defrost the AC

Turn the AC off.

• If your model has it, set it to Fan Only (no cooling) to help melt the ice faster.
• Place a towel under the unit or on the windowsill in case extra water drips while the ice melts.
• Let the AC sit until all ice has melted and the coils are clear and wet, not frosty.

Do not try to break or chip off the ice with sharp objects. This can damage the coils and void your warranty.

Step 2: Clean the air filter

A dirty filter is one of the most common causes of freezing.

• Turn the unit off and unplug it.
• Open the front panel. (On most TCL window ACs, it lifts or pulls forward.)
• Remove the air filter.
• Rinse the filter gently with lukewarm water until the dust is gone.
• Shake off excess water and let the filter air-dry completely.
• Once dry, place the filter back in, close the panel, and plug the unit back in.
• If your filter is damaged or won’t come clean, it may need to be replaced.

Step 3: Make sure air can flow freely

For your AC to work properly, it needs clear airflow:

• Move curtains, blinds, or furniture away from the front of the unit.
• Don’t place anything on top of the AC.
• Check outside the window to make sure the back of the unit isn’t blocked by plants, screens, or covers.
• Good airflow helps keep the coils at the right temperature so ice doesn’t form.

Step 4: Adjust your settings

After the unit has fully defrosted and the filter is clean:

• Turn the AC back on.
• Set it to Cool mode.
• Use a medium or high fan speed. This helps move cold air out into the room.
• Set the temperature to a reasonable level (for example, 72–76°F / 22–24°C), not the very coldest setting.
• Avoid running the unit on the lowest temperature and lowest fan speed for long periods, especially at night, as this can encourage ice to form again.

Step 5: Check the room and outdoor conditions

• Doors and windows closed: Make sure all windows and doors are closed while the AC is running so it can cool the room evenly.
• Correct room size: If the AC is much larger than the room (too many BTUs for a small space), it can cool the air too quickly and cause the coils to get too cold.
• Outdoor temperature: If it’s cool outside (around 60°F/16°C or lower), your window AC may freeze more easily. In that case, you may only need fan mode or no cooling.

When to contact TCL support

If your TCL window AC keeps freezing up even after:

• Defrosting the unit
• Cleaning the air filter
• Making sure airflow is not blocked
• Adjusting the temperature and fan settings
• …there may be an internal issue that needs professional service.

Please contact TCL support with:

• The model number and serial number of your AC
• A description of what you see (where the ice forms, how often, any error codes)
• Any steps you’ve already tried from this guide

We’ll be happy to review the situation and help with the next best steps.